I really don't understand what buffered means when describing concentrated sulfuric acid, or if this is delivered as a concentrate, with a buffering agent,that is then diluted and used.
This has come up on our forum before, and I really don't know the layman's solution to a spill on the floor. Sulfuric acid isn't going to evaporate when dried and Borek: has described how it will stay in equilibrium with the ambient humidity as a strong solution of sulfuric acid, which is at least a little bit hazardous.
But it can't float like a bead of mercury on a surface forever, either. Eventually, it will react with most surface coatings, reacting with and damaging them and eventually soaking into a porous surface somehow.
In the lab, when I have sulfuric acid, that I for some reason don't want anymore, I dilute it with water and neutralize with a weak base like sodium carbonate. And floor spills get cleaned up in the lab in that way.